I'm working on my second stand n its going to be a double stand for a 35g and a 33 g.
Based on this post, http://www.plantedtank.net/forums/showpost.php?p=1895781&postcount=97
having 4 supports equals out to be roughly 9240 lbs supported and taking 1/4th of that would give me 2310lbs to be supported by this stand, i will be putting these two tanks which should only weigh roughly 600 lbs together on the stand, so that said would this stand be stable given that his stands are much more distributed in the number of supports there are, but i am also putting less than half the weight he is projected to have.
Would this stand be strong enough, or additional bracing would be needed?
When in doubt, over build and brace. It should hold though. As a general rule I always overbuild. It's easier to soend an extra $1-3 on a extra 2x4 than staying up all night stressing your new stand will collapse!